Technical Data
MC68HC11E Family
—
Rev. 4
244
Electrical Characteristics
MOTOROLA
Electrical Characteristics
11.17 MC68L11E9/E20 Expansion Bus Timing Characteristics
Num
Characteristic
(1)
1. V
DD
= 3.0 Vdc to 5.5 Vdc, V
SS
= 0 Vdc, T
A
= T
L
to T
H
, all timing is shown with respect to 20% V
DD
and 70% V
DD
, unless
otherwise noted
2. Input clocks with duty cycles other than 50% affect bus performance. Timing parameters affected by input clock duty cycle
are identified by (a) and (b). To recalculate the approximate bus timing values, substitute the following expressions in place
of 1/8 t
cyc
in the above formulas, where applicable:
(a) (1
–
dc)
×
1/4 t
cyc
(b) dc
×
1/4 t
cyc
Where:
dc is the decimal value of duty cycle percentage (high time).
Symbol
1.0 MHz
Min
dc
2.0 MHz
Min
dc
Unit
Max
1.0
Max
2.0
Frequency of operation (E-clock frequency)
f
o
t
cyc
PW
EL
PW
EH
t
r
t
f
MHz
1
Cycle time
Pulse width, E low, PW
EL
= 1/2 t
cyc
–
25 ns
Pulse width, E high, PW
EH
= 1/2 t
cyc
–
30 ns
E and AS rise time
1000
—
500
—
ns
2
475
—
225
—
ns
3
470
—
220
—
ns
4a
—
25
—
25
ns
4b
E and AS fall time
—
25
—
25
ns
9
Address hold time
(2) (2)a
, t
AH
= 1/8 t
cyc
–
30 ns
Non-multiplexed address valid time to E rise
t
AV
= PW
EL
–
(t
ASD
+ 80 ns)
(2)a
Read data setup time
t
AH
95
—
33
—
ns
12
t
AV
275
—
88
—
ns
17
t
DSR
t
DHR
30
—
30
—
ns
18
Read data hold time , max = t
MAD
Write data delay time, t
DDW
= 1/8 t
cyc
+ 70 ns
(2)a
Write data hold time, t
DHW
= 1/8 t
cyc
–
30 ns
(2)a
Multiplexed address valid time to E rise
t
AVM
= PW
EL
–
(t
ASD
+ 90 ns)
(2)a
Multiplexed address valid time to AS fall
t
ASL
= PW
ASH
–
70 ns
Multiplexed address hold time, t
AHL
= 1/8 t
cyc
–
30 ns
(2)b
Delay time, E to AS rise, t
ASD
= 1/8 t
cyc
–
5 ns
(2)a
Pulse width, AS high, PW
ASH
= 1/4 t
cyc
–
30 ns
Delay time, AS to E rise, t
ASED
= 1/8 t
cyc
–
5 ns
(2)b
MPU address access time
(3)a
t
ACCA
= t
cyc
–
(PW
EL
–
t
AVM
)
–
t
DSR
–
t
f
MPU access time, t
ACCE
= PW
EH
–
t
DSR
Multiplexed address delay (Previous cycle MPU read)
t
MAD
= t
ASD
+ 30 ns
(2)a
0
150
0
88
ns
19
t
DDW
—
195
—
133
ns
21
t
DHW
95
—
33
—
ns
22
t
AVM
268
—
78
—
ns
24
t
ASL
150
—
25
—
ns
25
t
AHL
95
—
33
—
ns
26
t
ASD
120
—
58
—
ns
27
PW
ASH
220
—
95
—
ns
28
t
ASED
120
—
58
—
ns
29
t
ACCA
735
—
298
—
ns
35
t
ACCE
—
440
—
190
ns
36
t
MAD
150
—
88
—
ns